1. Field of the Invention
This invention relates generally to a method and apparatus for use in orthopedic surgery and, more particular, to a method and apparatus for providing a modular acetabular prosthesis having various modular attachment components for use during an orthopedic surgical procedure.
2. Discussion of the Related Art
A natural hip joint may undergo degenerative changes due to a variety of etiologies. When these degenerative changes become so far advanced and irreversible, it may ultimately become necessary to replace a natural hip joint with a prosthetic hip. When implantation of such a hip joint prosthesis becomes necessary, the head of the natural femur is first resected and a cavity is created within the intramedullary canal of the host femur for accepting the hip prosthesis. The hip prosthesis may be inserted and supported within the host femur by cementing the hip prosthesis within the host femur. Alternatively, the hip prosthesis may be impacted into the host femur so that it is snugly fit and supported by the host femur. If the acetabulum also needs repair, all remnants of articular cartilage are generally removed from the acetabulum and an acetabular prosthesis which will accommodate the head or ball of the hip prosthesis is affixed to the acetabulum. The acetabular prosthesis is affixed to the acetabulum by means of cement, screws or other appropriate fixation means.
Due to any number of reasons, however, a small portion of patients that undergo such orthopedic surgical procedures may require subsequent revision surgery to replace the prosthetic device with a new prosthetic device generally referred to as a revision prosthesis. In this regard, a revision acetabular prosthesis will generally include additional mounting points, such as integral flanges or hooks that provide additional stability for the revision acetabular prosthesis. These additional mounting points are generally required due to additional bone loss or defects exhibited at the acetabulum, such as collar/rim defects or pelvic discontinuity defects.
Various types of revision acetabular prostheses are currently available and different surgeons prefer different types of revision acetabular prostheses. Some surgeons prefer to use what is known as an ilium flange that is formed integral with the acetabular prosthesis and enables further securement of the acetabular prosthesis in the ilium region of the pelvis. Other surgeons prefer to use what is known as an obturator hook that is able to provide inferior fixation of the acetabular prosthesis by engaging the obturator foramen which is a large aperture adjacent the acetabulum. Because of this, a hospital must maintain a large inventory of different revision acetabular cups to meet the various surgeons"" preferences. Moreover, the surgeon will generally have to have several revision acetabular cups available during surgery to account for any type of condition that may arise during the surgical procedure. This increased inventory of prosthetic devices increases the overall hospital costs and inventory control. Furthermore, by requiring the multiple revision acetabular cups to be available during the surgical procedure, multiple prosthetic devices must be sterilized prior to the surgical procedure, thereby increasing the surgical time, cost and complexity.
What is needed then is a method and apparatus for providing a modular acetabular prosthesis having various modular attachment components for use during an orthopedic surgical procedure. This will, in turn, provide more surgical flexibility during implantation of the acetabular prosthesis, provide the surgeon with a variety of surgical options at the time of the surgical procedure, provide a universal acetabular cup that can be configured for use in many circumstances, reduce hospital inventory and inventory tracking requirements, and reduce the overall surgical time, cost and complexity. It is, therefore, an object of the present invention to provide such a method and apparatus for providing a modular acetabular prosthesis having various modular attachment components for use during an orthopedic surgical procedure.
In accordance with the teachings of the present invention, the method and apparatus for providing a modular acetabular prosthesis having a modular attachment component for use in orthopedic surgery is disclosed. The acetabular prosthesis includes an acetabular cup and a variety of modular attachment components. In this regard, a surgeon can select the appropriate modular attachment components depending on the patients needs, thereby providing a versatile acetabular prosthesis.
In one preferred embodiment, an acetabular prosthesis for implantation in an acetabulum is provided. The acetabular prosthesis includes an acetabular cup, an anti-rotation counterbore and a modular attachment component. The acetabular cup has an outer surface which is operable to be received in the acetabulum and an inner surface which is operable to receive a bearing liner. The anti-rotation counterbore is defined by the inner surface of the acetabular cup. The modular attachment component has an attachment member and an engagement member. The attachment member is operable to substantially nest within the anti-rotation counterbore and the engagement member is operable to engage a region of the acetabulum, such that upon positioning the attachment member in the anti-rotation counterbore the modular attachment component is inhibited from rotational movement relative to the acetabular cup.
In another preferred embodiment, an acetabular prosthesis for implantation in an acetabulum includes an acetabular cup, an attachment plate and a modular attachment component. The acetabular cup has an outer surface which is operable to be received in the acetabulum and an inner surface which is operable to receive a bearing liner with an annular region extending between the outer and inner surfaces. The attachment plate extends from the annular region and defines an internal channel having an internal key position with the internal channel. The modular attachment component has an attachment member and an engagement member. The attachment member is operable to be slidably received within the channel and positioned about the internal key. The engagement member is operable to engage a region of the acetabulum, such that upon the attachment member being slidably received in the channel, the modular attachment component is inhibited from rotational movement relative to the acetabular cup.
In yet another preferred embodiment, an acetabular prosthesis for implantation in an acetabulum includes an acetabular cup, at least one slot defined by the acetabular cup and a modular attachment component. The acetabular cup has an outer surface which is operable to be received in the acetabulum and an inner surface which is operable to receive a bearing liner. The one slot passes through the acetabular cup from the inner surface to the outer surface. The modular attachment component has an attachment member and an elongated blade. The attachment member is operable for use in attaching the modular attachment component to the acetabular cup and the elongated plate is operable to pass through the one slot to provide intermedullary fixation of the acetabular cup in a region about the acetabulum.
In another preferred embodiment, an acetabular prosthesis for implantation in an acetabulum includes an acetabular cup, at least one bore defined by the acetabular cup, a rotational member and a modular attachment component. The acetabular cup has an outer surface which is operable to be received in the acetabulum and an inner surface which is operable to receive a bearing liner. The one bore passes from the inner surface to the outer surface and includes a rotational sidewall. The rotational member is operable to mate with at least a portion of the rotational sidewall of the bore. The modular attachment component is in communication with the rotational member, such that the modular attachment component is operable to be pivoted relative to the acetabular cup as the rotational member engages the rotational sidewall.
In yet another preferred embodiment, an acetabular prosthesis for implantation in an acetabulum includes an acetabular cup, a pivot bore, a plurality of engagement bores and a modular attachment component. The acetabular cup has an outer surface which is operable to be received in the acetabulum and an inner surface which is operable to receive a bearing liner. The pivot bore is defined by the acetabular cup and the plurality of engagement bores is also defined by the acetabular cup, such that the plurality of engagement bores is positioned circumferentially about the pivot bore and extending through the acetabular cup. The modular attachment component includes an attachment member and an engagement member. The attachment member is operable to be pivotably secured relative to the pivot bore and the engagement member is operable to engage a plurality of regions about the acetabulum.
In still another preferred embodiment, a method for implanting an acetabular prosthesis having a modular attachment component in the acetabulum is provided. This method includes providing an acetabular cup that has an outer surface and an inner surface, engaging the outer surface of the acetabular cup with a surgically prepared portion of the acetabulum, locating a punch guide along the inside surface of the acetabular cup, guiding a punch through the acetabular cup and into the acetabulum to form a hole in the acetabulum, removing the punch and punch guide from the acetabular cup, passing a portion of the modular attachment component through the acetabular cup and into the hole formed by the punch, and securing the modular attachment component to the acetabular cup.
Use of the present invention provides a method and apparatus for providing a modular acetabular prosthesis. As a result, the aforementioned disadvantages associated with the currently available acetabular prosthesis have been substantially reduced or eliminated.